iClosed direct integration with Linq gives you a cutting-edge messaging workstation.
Every message routes securely through Linq’s smart infrastructure, retaining absolute native authority, tracking delivery events, and utilizing automated fallback routes.
Integration is available with Growth and Business subscription plans - check out full breakdown here.
Step-By-Step Guide
Navigate to 
Integrations page and click on the Linq integration to start.
Linq integration consists of two core phases:
Integration - connecting with the API key from Linq, and
Post-connection workspace configuration
Step 1 - Integration
To grant iClosed permission to go to Linq acoount and copy API key, as Linq operates on a single unified API account token pattern:
Log into your Linq account and go to API → Overview → API Tooling.
Click on the Generate new token to create your V3 API token.
Go back to iClosed and paste it in the box
Click the "Done" button to finish integrations part.
Pro Tips
In case the connection can't be established for any reason, you will receive a Conection failed.
Double-check if you've accidentally pasted trailing empty spaces into the password or token rows. If the token match continues to reject create a fresh API key or reach out to iClosed customer support team via chat button.
Step 2 - Post-Connection Workspace Configuration
Once the apps are connected the next step is to configure phone number and chat management:
Phone Number Configuration
Select the default phone number you'd like to send messages from.
A conversation always continues with the same number it was started on unless it’s blocked. Here's a bulleted breakdown of the phone number tied to the conversation logic:
Changing your Linq number only applies to new conversations.
If a number hits the daily limit (50 new conversations), new chats cannot be started from this line until the limit resets
Limit resets at 4pm EST every day
Ongoing conversations remain unaffected
Automatically switch phone numbers when daily quota is reached
When the checkbox is selected, iClosed will switch between all available Linq phone numbers.
When the checkbox is not selected, iClosed will send messages only from the number selected as default line.
Pro Tips
If you've added additional phone numbers in Linq, make sure to click on the resync button on the integrations page.
Resyncing the channel will update the phone lines.
If a phone number is deactivated in Linq, but the chat has started already, first active available phone number will take over.
Create chats for non-contacts
When enabled, inbound messages from contacts that are not in iClosed Global Data will be created along with new chat added to the Unified Inbox.
Unlike Gmail and Outlook, it is highly recommended to keep this checkbox ON for the Linq integration as the Linq account is managed at the team level.
Any new incoming message represents a fresh, inbound lead that your business should have in iClosed Unified Inbox.
Disconnecting Linq Integration
In case you ever need to link a completely separate Linq account or permanently remove this channel from your iClosed account, here's how to do it:
Navigate to the integrations under Integrations → Linq
Click the "Delete Channel" button on the right-hand side of the screen
A system confirmation modal will pop up on your screen asking you to confirm: "Are you sure you want to delete this channel?"
Click the "Delete" button to disconnect or cancel to withdraw request
Important Notes
What happens when you disconnect Linq?
All previously synchronized threads, text conversations, and attached asset media records remain securely logged inside your contacts' timelines - no sales history is removed.
You will instantly lose the power to write, draft, or send messages out from that number from within the iClosed Message Composer interface.
Any active Automated Workflows relying on an iMessage action block linked to this line will immediately throw an execution pause state. Remember to re-map your automation cards immediately upon re-connection!
Messaging Costs, Daily Message and Monthly Conversation Caps
Your monthly active conversation allowance and chat history retention scale directly with your subscription tier.
Channels like Linq and Sendblue are exclusively available on the Growth and Business tiers. Your monthly active conversation limits (300 on Growth / 1,000 on Business) and history retention lengths are determined strictly by your active plan.
A conversation is counted as active once it registers messaging activity within that calendar month.
Closing or deleting a chat will not lower your count for the current month. Once a contact messages you (or you message them) and uses up one of your monthly slots (e.g., 300 on Growth or 1,000 on Business), that slot is locked in until the counter resets next month.
It does not operate like a phone line where you can just hang up on one person to talk to another. It tracks the total unique volume of conversations handled across the entire month and rollover of unused conversations is not available.
Extra monthly conversations available upon inquiry to the support team.
Additionally, Linq enforces specific message caps and volume limits to prevent spam and ensure line safety. These include:
Daily Contact Limit - There is a 50 unique new contacts limit that you can message per phone line, daily.
Consecutive SMS Limit - Outbound messages are capped at 150 consecutive messages per line. This limit cannot be bypassed.
Character Limit - Individual message content cannot exceed 18,996 characters. If you exceed this, you will need to break the message into multiple parts
FAQs
Is there a phone line daily cap?
Is there a phone line daily cap?
Yes, there is a 50/messages per phone line for new contacts daily. Additional Linq thresholds and recommendations are:
Recommended Daily Target: Linq advises keeping your message volume under a combined total of 7,000 inbound and outbound messages per day per line. Anything north of that target won't be blocked, but it risks minor performance lag.
Per-Recipient Rate Limit: The system enforces a standard rate cap of 30 messages per 60-second window to any single, unique contact pair. This is strictly a safety feature designed to stop rapid automated message loops or double-sending bugs from spamming a customer's phone.
What are the benefits of using Linq?
What are the benefits of using Linq?
Premium Apple iMessage Execution: Deliver crisp blue bubbles, real-time typing indicators, native emoji reactions, and read receipts to iPhone users.
Rich RCS Messaging for Android: Reach Android users using advanced RCS protocols rather than stripped-down, flat SMS text blocks.
Smart SMS/Voice Fallback: Automatically switches to high-deliverability SMS if a lead is on an older device or outside cellular data zones.
Learn More